Baby Huey build log.

2015

November,

Huey is printing fairly well.
He still has some warped and cracked version one (printrbot printed) parts which are long over due being replaced with version three self printed ones.
Mainly I'm talking about Z bearing assemblies.
I've had a lot of trouble printing these due the level shifts 3/4 of the way through.
With .4mm tips they are 8.5 hours prints - errors after 6 hours aren't fun.

My level shifts have been almost cured by replacing my stepper drivers.
The originals used Stepstick A4988 based modules.
The new ones are DRV8825 based.
I can run there a bit harder but unfortunately the chips are not in the same places on the modules so my cooling ports aren't in the right places.

In the last few days I've made some "dry boxes" to keep the moisture out of my filament while printing.

PETG is now one of my favorite plastics apart from the price.

It has low curl like PLA but it is stronger and can handle higher temperatures.
I'm using glue-stick on the printbed for small jobs and spray adhesive for big jobs.
PETG must be kept dry. Over time damp PETG seems to dry out if kept in a dry room temperature environment.

For really strong prints I use nylon - I've had fairly good results with 3mm weed trimmer cord.
Nylon's big vice is curl. It sticks well to paper but curls worse than ABS.
Its other vice is moisture. It pulls water out of the air in no time. I've found it really has to be heated to dry it out.

The newer versions of repetier have also "fixed" the USB issues.

Huey is just completing a 8.5 hours ZBA print - no level shifts and printed using USB not the SD card.

Another change I made it to replace some of the ratty zinc plated M6 Z rods with stainless steel ones.
I also used some brass nuts. This was an improvement but to my surprise the brass nuts worn out in a few months.
I have some stainless steel one on order.

July,

There have been upgrades and improvements even if I don't report them all.
I now have a collection of hotends including two E3D volcanos.
The main carriage is now combined with the extruder.
The hotends plus fans now plug in as a module.
Only two screws and one plug to change over - easier than changing a nozzle.
One hotend is for 1.75mm because I couldn't find affordable HIPS in 3mm.
I really like HIPS now.
Also printed PETG, bridge nylon and weed trimmer line.
All fairly good but must be dried and kept dry.
The trimmer line curls on big jobs and might benifite from a hotbed and heated enclosure.

January.

3rd.
Still not good. I think the extrusion is coming out cool even when slowed to 40mm/sec
The print of the electronics box is weak and splits easily.
I have a lot of repairing to do and getting peeved.
The box was an 8 hour print and the lid was 5 hours.
Small tests came out good because slic3r slows to head down to allow cooling between layers.

2014

December.

11th - SD working.

One of the "good" SD apapters arrived today.
Not sure where from becuase it wasn't marked.
I also got a call from Australia post today.
They have an overseas parcel addressed to "Eddie Australia".
Some senders are clueless.
Anyway SD is working so a big print is planned for tomorrow.

10th - extruder test.

I found I had to slow down to 40mm/sec to get a good flow with a .6mm nozzle and .4mm layers.

8th

The new teensy has arrived but no SD adapters yet.
USB is still crashing.
I'm having no luck printing fast with the .6mm nozzle.
I think the hotend just can't melt filtament fast enough.
The printer has no trouble running at 130mm per second but the extruder can only run at half that.
It can do short runs at 130mm but after a few seconds the output slows down.
Run too fast and the extruder stepper looses steps.
The nozzle temperature stays good so it isn't a heater problem.
These J-head's feature a short melt zone - good for small detailed prints but not good for supplying high volumes of molten plastic.

November

26th

I still can't print reliably over USB.
I bought a SD card adapter from Ebay but can't get it to work.
The card work on printrboard and should be OK so it is either the adapter or the frimware.
My guess is firmware. I've tried recompiling with SD support but so far no luck.
A spare teensylu is on the way and it will be easier to capture SD signals when I have it.
Later.
These adapter clearly won't work on the teensy.
There are a lot of listings for SD adapters for ramps/teensylu but the pinouts are clearly for RAMPS and the teensylu is quite different.
I can possibly adapt the adapter if I know what pins the teensy uses for SD.
Even later.
I ordered a couple of adapters which look correct.
One from newegg for $8 and one from amazon for twice that.
I had already ordered a bunch of ramps type boards but they are so cheap ($2.50) it isn't worth the time asking for a refund.
So if you are after an adapter for the teensylu make sure there is no meantion of "ramps" and if they have a picture check the location of the vcc pin to verify it isn't for ramps.
On ramps vcc is on the board edge for teensy it isn't.

9th Good news and not so good news.

Good - The ZBA printed without crashing.
Not - There was some shifting in the Y axis.
Good - It was usable.
Not - It cracked when the rods went it.
Good - Found some of the reason for the jerky Y motion.
Not - The short moving rod is about 1mm to long.
Good - With the new ZBA it is printing better than before.
Not - One Z bearing it not in contact with the rail.

There are several options for fixing the problem with grinding the rod down being the obvious one.
Seeing the printer is working as is my plan is to ignore it for now and print another ZBA.
When the ZBA is fitted I'll put some spacers in the corner peices to make Huey one or two MM larger in the Y driection.

The next ZBA has some minor mods - the main one is the addition of some guides for putting zipties around the rod holders to reduce spreading if it cracks.

The last ZBA has embedded flower nuts to allow the rods to be clamped with screws - I haven't try this yet.

6th

Half way throught a 8.5hr print.
So far so good. There are storms outside and I'm hoping there are no power glitches.
I mananged to get the linux version of repetier to work and it doesn't seem to have the memory issue I had with XP.
I've had some extruder probs but so far so good tonight.
The job is version-2 of the Z bearing assembly - the replace the wobbly one in use now.
My $1.50 sd cards arrived and I got them working on the printrbot so I should have a few options for doing big print jobs.

4th

Still too unreliable for serious work.
I thought I might be able the print using my XP netbook but it ran out of memory.
I've tested most parts of the system and can't pin it down to one thing.
It may be some thing like a ground loop picking up noise.
I have an atom based win7 box I could try but printing from SD card may be the answer.
I've found SD adaptors for the teensy and ordered one.

I've also fitted a new Huey made extruder which uses rubber bands instead of springs.
There is still a Y motion problem and I've removed one Y bearing to see what happens.

The worst part in Huey ATM is the front left Z-bearing assembly.
ZBA version two is ready to print when Huey is up to it.
Some video has been edited but no voice-over yet.

October.

October-30th

It is printing fairly well.
No miss-stepping and good success bonding ABS to the cold bed.
(later - it wasn't miss stepping - the shifting was from the front left ZBA being bad.)
Mostly I use PLA.
The biggest problem is the system seems to crash every 2 or 3 hours so I can't do the big parts I want to redo.
I'm driving it via a USB extention which might be part of the problem.
However I think I had problems with the printrbot too when I move from the old XP machine to the win-8 quad core.

I will try running off the xp netbook but maybe give Huey a bit of a rest.
It was big push to get this far and need to do some other things.
I'll put togther some video within a week or two I hope.

October-26th

A few problems have turned up, some minor some not.
The most serious is occasional miss-stepping.
I think this is a problem with the electronics and not the mechanical stuff.
It was sensitive to noise on the 230V mains but that seemed to be less of an issue after I cut the USB power line.
I suspect the interupt (ie step signal) is picking up noise.
If so this should be easy to fix but I haven't tackled it yet.
The issue hasn't occured for several hours now and I'm not sure if it has gone away or not.

My first problem wss lack off airflow to the extruder stepper driver.
After a quick size and flowrate calibration Huey's first real job was a fan holder.
The second issue was with the extruder filament guide was not stopping the filament drifting to the side and jamming.
Huey printed the modified pressure roller/guide which solved the problem.

The next problem was the X and Y steppers were getting hot. I used several fans to improvise then designed and printed a clip on fan mount for 40mm fans. Due to lack of fans only one has been fitting and it works perfectly.

The remaining problem is head travel in the Y direction is not as smooth as the X. I'm still investigating this one.
The prints are fairly good but I'd like to solve the mystery before it bites on a big job.

23rd. It works.

The first test print was done this afternoon.
I'm already printing a temporary fan mount, self improvement has already begun.
There is a minor problem with the Y enable line being stuck active and lack of cooling on the extruder stepper driver.
When printing slowly Huey's quality already looks like it exceeds that of the printrbot and is quite capable of reprapping.
I'm still tweaking and calibtating.
It is a bit wobbly at high speed but definitely good enough to do what it was designed for - rough large prints.

22nd.

The power supply failed.
I replaced it. I reflashed the boot into an old arduino pro-mini and it worked fine for the Y axis board.
Finished wiring and replaced the bad motor.
It moves and homes on all axes.
I need to set up a print bed and I should be able to test.

21st. ARRGGGHH!!

I have Z and X axis working.
However I've blown 3 micros (dx.com auduino pro-mini) and at least one stepper driver in the process.
Several tants blew as well (correct polarity in case you are wondering).

The first micro went at same time as a tant (when powering up the X go between the first time).
A blown tant shouldn't blow a micro but freaky things happen sometimes.
A different pro-mini worked fine as a replacement.
One of the stepper drivers was also dead.

The another one went after I swapped micros (I'm not programming them in situ so I'm swapping them around).
I blamed it on plugging it in offset even though I thought I had it right.

Then the third failed when I powered the last board (the Y axis).
This time I knew it was in correctly.

I then noticed all the dead ones were the same type and the two good ones were different.
I suspected the on board voltage regulators and sure enough instead of 5V output they had 10V.
This also explains the dead stepper driver because the low voltage pins are rated at 5.5V

So close to finishing but I now have to find another minipro.

Ironically the cheapest ($4) pro-minis work - it was the slightly less cheap ($5ish) ones which died.

15th.

The PCBs are finally here - slowler to arrive than the first batch.
Might start build today or tomorrow.

September.

20th. Extruder works.

The extruder works. It needs some tweaking to insulate the sensor wires from the hotend.
Some of my ducting melted but no show stopper.
I extruded some ABS and it looks good.

I'm hoping for the new PCBs in two weeks along with some other parts.
I think it will take a week to put everything together and do the first test print.

I've also redone some of the electronics case CAD I lost in the crash. This will be the first big print for Huey if he is up to it.

15th.

I've had a frustrating time compiling and uploading to repetier firmware.
I got it mostly working a few days ago but had crazy stuff happening with the Z-limit signal from the go-between board.
The board works but repetier would ignore it - but sometimes a finger in the right place would get it too work.
Trying all the usual stuff but in the end it was solved with intuition not logic.

The firmware seems to be reading the Y-stop pin instead of the Z-stop pin.
Presumably an error in pins.h but strange that no-one else is complaining.

9th.

One Y motor seems faulty but the two X motors seem to work perfectly.
The little steppers seem to have enough power but I haven't tried with the weight of the extruder.

8th.

Two Z motors running and the homing logic seems OK but repetier isn't responding to the signal.
I will need to install arduino IDE and jump throught the compile upload hurdles again.
I lost my current config in the drive crash so I have to do it all again.

Testing the X or Y motors is probably more important because I may need to order bigger motors.

6th.

New PCB submited to dirtyPCBs for fab.
I found several bugs in version-1 mostly in my arduino footprint.
I added options for a seperate 5V regulator, LEDs and some unnessecary protection resistors.
V1 has only been tested with one z-motor so far and runs OK at 6400 microsteps/sec (2 rmp).
The Z motors look like they will work but the drivers get hot and really need some fan cooling.

The motor was controlled by repetier host on my netbook talking to repetier firmware in a teensylu.

The step,direction and enable signal were taped at empty driver socket on the teensylu and jumpered to my PCB.
The basic idea seems to have legs.

2nd.

Some progress but not all good.
The carriage and hot-end was made a few weeks ago but I'm leaving the heater and sensor off till I have the carriage moving.
I recovered a fairly up to date copy of the PCB artwork and brought it up to date.
However when I powered up my prototype PCB I had trouble with an FEC (flame emmiting capacitor).
No mystery there as I had it reversed but no idea why a second cap charred and the arduino died.
A replacement arduino also died.
I've done a new version of the PCB artwork but until I know why the current one is failing I won't submit it for manufacture.

The flame out co-incided with me catching a virus (human not PC) and I've been taking it slow.

September.

20th. Extruder works.

The extruder works. It needs some tweaking to insulate the sensor wires from the hotend.
Some of my ducting melted but no show stopper.
I extruded some ABS and it looks good.

I'm hoping for the new PCBs in two weeks along with some other parts.
I think it will take a week to put everything together and do the first test print.

I've also redone some of the electronics case CAD I lost in the crash. This will be the first big print for Huey if he is up to it.

15th.

I've had a frustrating time compiling and uploading to repetier firmware.
I got it mostly working a few days ago but had crazy stuff happening with the Z-limit signal from the go-between board.
The board works but repetier would ignore it - but sometimes a finger in the right place would get it too work.
Trying all the usual stuff but in the end it was solved with intuition not logic.

The firmware seems to be reading the Y-stop pin instead of the Z-stop pin.
Presumably an error in pins.h but strange that no-one else is complaining.

9th.

One Y motor seems faulty but the two X motors seem to work perfectly.
The little steppers seem to have enough power but I haven't tried with the weight of the extruder.

8th.

Two Z motors running and the homing logic seems OK but repetier isn't responding to the signal.
I will need to install arduino IDE and jump throught the compile upload hurdles again.
I lost my current config in the drive crash so I have to do it all again.

Testing the X or Y motors is probably more important because I may need to order bigger motors.

6th.

New PCB submited to dirtyPCBs for fab.
I found several bugs in version-1 mostly in my arduino footprint.
I added options for a seperate 5V regulator, LEDs and some unnessecary protection resistors.
V1 has only been tested with one z-motor so far and runs OK at 6400 microsteps/sec (2 rmp).
The Z motors look like they will work but the drivers get hot and really need some fan cooling.

The motor was controlled by repetier host on my netbook talking to repetier firmware in a teensylu.

The step,direction and enable signal were taped at empty driver socket on the teensylu and jumpered to my PCB.
The basic idea seems to have legs.

2nd.

Some progress but not all good.
The carriage and hot-end was made a few weeks ago but I'm leaving the heater and sensor off till I have the carriage moving.
I recovered a fairly up to date copy of the PCB artwork and brought it up to date.
However when I powered up my prototype PCB I had trouble with an FEC (flame emmiting capacitor).
No mystery there as I had it reversed but no idea why a second cap charred and the arduino died.
A replacement arduino also died.
I've done a new version of the PCB artwork but until I know why the current one is failing I won't submit it for manufacture.

The flame out co-incided with me catching a virus (human not PC) and I've been taking it slow.

August.

7th.

Making some progress again.
Printrbot is working on the new PC.
After installing the new version of repetier host PLA is printing better than before the crash.
ABS is not printing well but that is fairly normal and ABS doesn't like the cold.
I redid the CAD files for the printhead carriage and I think it is better than the one I lost.
However it didn't print well in ABS.
Only a small part needs to be ABS so I'm rethinking the design and will probably split the part so the bulk is PLA.

July.

27th minor disaster.

I had a disk crash last night. Probably a month set back. Not only did I loose a lot of files but I also have to set up a new PC.
My XP box is now dead.

19th

I got the repetier firmware compiled after jumping through all the required hoops.
I still couldn't get the bootloader(s) to work and programmed the usb1286 with an ISP programmer.
That had issues as well - I had to 1/2 the programmer clock speed before I could read the correct device ID and enter programming mode.
The firmware runs and talks to the host but there will probably be a few more times through the compile/upload cycle before all the options are correct.
First time around the hotbed sensor didn't work and I had to edit Configuration.h

18th

Two set backs.
The PCB footprints for the stepper driver modules are too wide - 0.6 inch instead of 0.5
Not a show stopper just ugly. I've fixed the PCB artwork.

Next the Teensylu arrived but I haven't managed to compile or upload code into it.
I can't download "Arduino 1.0.5" for some reason and it is the only version supported by teensyduino.

17th

The go-between PCBs have arrives from dirtyPCBs and look good.
The hot-end kit is here but I haven't opened the box yet.
Still short on connectors and cables but I can make a start on testing my boards.
I also made (printed) a mount for the PSU.
I'm part way through designing the case for the electronics but it is 450mm long and can't be printed on my small printer.

9th

Designed, printed and fitted temporary limit switch carriers and Z-micro switch landing area.
All ad-hock because the next generation z bearing assembly will incorporate them.
I decided to put the Z-switches on the Z carriage not the base.
There are already X and Y switches mounted there so I may as well run the cables together.

5th

3rd

PCBs are in the mail.
I also wrote the code for them but not tested yet.
In the last few days I designed the belt coupling for the X and Y rods ends.

I noticed a difference in belt positions between X and Y belts.
This turned out the be because the Z-bearing assemblies are drooping.
I don't think this is a show stopper and the next version will be larger and more stable.

June.

27th

The homebrew PCB didn't happen due to an aerosol can failure.
So I ordered 10 dirty PCBs on the 25th from http://dirtypcbs.com
Worst case delivery could be 8 weeks but if I'm lucky it will be less than 1/2 that.
I also started writing the code for it and noticed a minor problem.
The AVR pin-change interrupts can't be used to detect only rising edges (they detect both edges).
Fixing this in software would slow things down so I'll just short the pin change input (a5) to int0 (d2).
I'll also add a "homed" LED if I ever update the artworks.

23rd

Ordered a Teensylu v0.8 because it has easy access to the signals I need. Uploading the firmware looks like a pain though.

Phil is going to try making a DIY PCB for me in the next few days. If it works I'll be ordering some dirtcheap PCBs.

22nd - Go between PCB.

I've done very little on the mechanical stuff and worked on the control stuff.
I wanted to move away from using EAGLE for the PCB stuff because of the board size limitation of the free version.
I wasted quite a lot of time trying to install linux mint 16 so I could try jEDA as an alternative. After many installer failures I move to windows Kicad instead. It has its quirks and annoyances but it one of the easiest PCB packages I've used. Today I finished the first version of the go-between board.
See the main page for more info on what that is.

May

30th

23rd

All four Z-bearing assemblies are hanging off the threaded rods. Only one Z-motor fitted ATM.
Tolerances around the Z motor couplings are tight and I went through many revisions to get it rotating freely.

18th

All Z-bearing assemblies installed including the four motors and four idlers.
I also worked out how I can (eventually) use eight limit switches and eight stepper controllers with a printrboard.

16th

I had problems with a warped wooden bed on the printrbot and had to make mods to fix it.
I have since printed 4 versions of the two bearing Z assembly.
They are fitted and look Ok except the 12mm rod holes are a little shallow.
I deepened them to 15mm in the model and deepened some physical hole with a 12mm drill.

6th

I fought with Sketckup for 3 long days converting the Z bearing thing to a two bearing version.
Only Sketchup users know how hard it can be to fix a model that has gone bad.
In the process I converted to sketchup "make" version and "solid inspector" plugin saved me hours.

Also made a new printbed for the printrbot and it is too uneven to use - yet another job to do.
So the two-bearing design is ready to print but will have to wait till I have a new bed.

3nd

Well that was pretty basic. One bearing was being jammed by the end of the motor shaft.
Either the motor is moved back, the motor is moved sideways or the shaft is shortened.
I think I will go with option two. The motor plate probably needs tweaking anyway.

I'd still like to try a two (not four) bearing version of the Z bearing thing.

Pretty much wasted a day trying to modify the art work for two bearings - it it a mess and not even 1/2 done.

The new motor plate has a problem with access to one motor screw - can live with that for the beta.

I thought it might be the belt tension twisting the assembly but that isn't it. Will investigate tomorrow.
It is possible the inner bearing may not be needed.
This assembly was dropped a few weeks ago and may be damaged.
It is printed in PLA and had issue with the bridges and these sags may be interfering with the bearings.

1st

T5 idler pulley designed and tested.

April

Frame assembled.

Frame props made

2014

December.

11th - SD working.

One of the "good" SD apapters arrived today.
Not sure where from becuase it wasn't marked.
I also got a call from Australia post today.
They have an overseas parcel addressed to "Eddie Australia".
Some senders are clueless.
Anyway SD is working so a big print is planned for tomorrow.

10th - extruder test.

I found I had to slow down to 40mm/sec to get a good flow with a .6mm nozzle and .4mm layers.

8th

The new teensy has arrived but no SD adapters yet.
USB is still crashing.
I'm having no luck printing fast with the .6mm nozzle.
I think the hotend just can't melt filtament fast enough.
The printer has no trouble running at 130mm per second but the extruder can only run at half that.
It can do short runs at 130mm but after a few seconds the output slows down.
Run too fast and the extruder stepper looses steps.
The nozzle temperature stays good so it isn't a heater problem.
These J-head's feature a short melt zone - good for small detailed prints but not good for supplying high volumes of molten plastic.

November

26th

I still can't print reliably over USB.
I bought a SD card adapter from Ebay but can't get it to work.
The card work on printrboard and should be OK so it is either the adapter or the frimware.
My guess is firmware. I've tried recompiling with SD support but so far no luck.
A spare teensylu is on the way and it will be easier to capture SD signals when I have it.
Later.
These adapter clearly won't work on the teensy.
There are a lot of listings for SD adapters for ramps/teensylu but the pinouts are clearly for RAMPS and the teensylu is quite different.
I can possibly adapt the adapter if I know what pins the teensy uses for SD.
Even later.
I ordered a couple of adapters which look correct.
One from newegg for $8 and one from amazon for twice that.
I had already ordered a bunch of ramps type boards but they are so cheap ($2.50) it isn't worth the time asking for a refund.
So if you are after an adapter for the teensylu make sure there is no meantion of "ramps" and if they have a picture check the location of the vcc pin to verify it isn't for ramps.
On ramps vcc is on the board edge for teensy it isn't.

9th Good news and not so good news.

Good - The ZBA printed without crashing.
Not - There was some shifting in the Y axis.
Good - It was usable.
Not - It cracked when the rods went it.
Good - Found some of the reason for the jerky Y motion.
Not - The short moving rod is about 1mm to long.
Good - With the new ZBA it is printing better than before.
Not - One Z bearing it not in contact with the rail.

There are several options for fixing the problem with grinding the rod down being the obvious one.
Seeing the printer is working as is my plan is to ignore it for now and print another ZBA.
When the ZBA is fitted I'll put some spacers in the corner peices to make Huey one or two MM larger in the Y driection.

The next ZBA has some minor mods - the main one is the addition of some guides for putting zipties around the rod holders to reduce spreading if it cracks.

The last ZBA has embedded flower nuts to allow the rods to be clamped with screws - I haven't try this yet.

6th

Half way throught a 8.5hr print.
So far so good. There are storms outside and I'm hoping there are no power glitches.
I mananged to get the linux version of repetier to work and it doesn't seem to have the memory issue I had with XP.
I've had some extruder probs but so far so good tonight.
The job is version-2 of the Z bearing assembly - the replace the wobbly one in use now.
My $1.50 sd cards arrived and I got them working on the printrbot so I should have a few options for doing big print jobs.

4th

Still too unreliable for serious work.
I thought I might be able the print using my XP netbook but it ran out of memory.
I've tested most parts of the system and can't pin it down to one thing.
It may be some thing like a ground loop picking up noise.
I have an atom based win7 box I could try but printing from SD card may be the answer.
I've found SD adaptors for the teensy and ordered one.

I've also fitted a new Huey made extruder which uses rubber bands instead of springs.
There is still a Y motion problem and I've removed one Y bearing to see what happens.

The worst part in Huey ATM is the front left Z-bearing assembly.
ZBA version two is ready to print when Huey is up to it.
Some video has been edited but no voice-over yet.

October.

October-30th

It is printing fairly well.
No miss-stepping and good success bonding ABS to the cold bed.
(later - it wasn't miss stepping - the shifting was from the front left ZBA being bad.)
Mostly I use PLA.
The biggest problem is the system seems to crash every 2 or 3 hours so I can't do the big parts I want to redo.
I'm driving it via a USB extention which might be part of the problem.
However I think I had problems with the printrbot too when I move from the old XP machine to the win-8 quad core.

I will try running off the xp netbook but maybe give Huey a bit of a rest.
It was big push to get this far and need to do some other things.
I'll put togther some video within a week or two I hope.

October-26th

A few problems have turned up, some minor some not.
The most serious is occasional miss-stepping.
I think this is a problem with the electronics and not the mechanical stuff.
It was sensitive to noise on the 230V mains but that seemed to be less of an issue after I cut the USB power line.
I suspect the interupt (ie step signal) is picking up noise.
If so this should be easy to fix but I haven't tackled it yet.
The issue hasn't occured for several hours now and I'm not sure if it has gone away or not.

My first problem wss lack off airflow to the extruder stepper driver.
After a quick size and flowrate calibration Huey's first real job was a fan holder.
The second issue was with the extruder filament guide was not stopping the filament drifting to the side and jamming.
Huey printed the modified pressure roller/guide which solved the problem.

The next problem was the X and Y steppers were getting hot. I used several fans to improvise then designed and printed a clip on fan mount for 40mm fans. Due to lack of fans only one has been fitting and it works perfectly.

The remaining problem is head travel in the Y direction is not as smooth as the X. I'm still investigating this one.
The prints are fairly good but I'd like to solve the mystery before it bites on a big job.

23rd. It works.

The first test print was done this afternoon.
I'm already printing a temporary fan mount, self improvement has already begun.
There is a minor problem with the Y enable line being stuck active and lack of cooling on the extruder stepper driver.
When printing slowly Huey's quality already looks like it exceeds that of the printrbot and is quite capable of reprapping.
I'm still tweaking and calibtating.
It is a bit wobbly at high speed but definitely good enough to do what it was designed for - rough large prints.

22nd.

The power supply failed.
I replaced it. I reflashed the boot into an old arduino pro-mini and it worked fine for the Y axis board.
Finished wiring and replaced the bad motor.
It moves and homes on all axes.
I need to set up a print bed and I should be able to test.

21st. ARRGGGHH!!

I have Z and X axis working.
However I've blown 3 micros (dx.com auduino pro-mini) and at least one stepper driver in the process.
Several tants blew as well (correct polarity in case you are wondering).

The first micro went at same time as a tant (when powering up the X go between the first time).
A blown tant shouldn't blow a micro but freaky things happen sometimes.
A different pro-mini worked fine as a replacement.
One of the stepper drivers was also dead.

The another one went after I swapped micros (I'm not programming them in situ so I'm swapping them around).
I blamed it on plugging it in offset even though I thought I had it right.

Then the third failed when I powered the last board (the Y axis).
This time I knew it was in correctly.

I then noticed all the dead ones were the same type and the two good ones were different.
I suspected the on board voltage regulators and sure enough instead of 5V output they had 10V.
This also explains the dead stepper driver because the low voltage pins are rated at 5.5V

So close to finishing but I now have to find another minipro.

Ironically the cheapest ($4) pro-minis work - it was the slightly less cheap ($5ish) ones which died.

15th.

The PCBs are finally here - slowler to arrive than the first batch.
Might start build today or tomorrow.

September.

20th. Extruder works.

The extruder works. It needs some tweaking to insulate the sensor wires from the hotend.
Some of my ducting melted but no show stopper.
I extruded some ABS and it looks good.

I'm hoping for the new PCBs in two weeks along with some other parts.
I think it will take a week to put everything together and do the first test print.

I've also redone some of the electronics case CAD I lost in the crash. This will be the first big print for Huey if he is up to it.

15th.

I've had a frustrating time compiling and uploading to repetier firmware.
I got it mostly working a few days ago but had crazy stuff happening with the Z-limit signal from the go-between board.
The board works but repetier would ignore it - but sometimes a finger in the right place would get it too work.
Trying all the usual stuff but in the end it was solved with intuition not logic.

The firmware seems to be reading the Y-stop pin instead of the Z-stop pin.
Presumably an error in pins.h but strange that no-one else is complaining.

9th.

One Y motor seems faulty but the two X motors seem to work perfectly.
The little steppers seem to have enough power but I haven't tried with the weight of the extruder.

8th.

Two Z motors running and the homing logic seems OK but repetier isn't responding to the signal.
I will need to install arduino IDE and jump throught the compile upload hurdles again.
I lost my current config in the drive crash so I have to do it all again.

Testing the X or Y motors is probably more important because I may need to order bigger motors.

6th.

New PCB submited to dirtyPCBs for fab.
I found several bugs in version-1 mostly in my arduino footprint.
I added options for a seperate 5V regulator, LEDs and some unnessecary protection resistors.
V1 has only been tested with one z-motor so far and runs OK at 6400 microsteps/sec (2 rmp).
The Z motors look like they will work but the drivers get hot and really need some fan cooling.

The motor was controlled by repetier host on my netbook talking to repetier firmware in a teensylu.

The step,direction and enable signal were taped at empty driver socket on the teensylu and jumpered to my PCB.
The basic idea seems to have legs.

2nd.

Some progress but not all good.
The carriage and hot-end was made a few weeks ago but I'm leaving the heater and sensor off till I have the carriage moving.
I recovered a fairly up to date copy of the PCB artwork and brought it up to date.
However when I powered up my prototype PCB I had trouble with an FEC (flame emmiting capacitor).
No mystery there as I had it reversed but no idea why a second cap charred and the arduino died.
A replacement arduino also died.
I've done a new version of the PCB artwork but until I know why the current one is failing I won't submit it for manufacture.

The flame out co-incided with me catching a virus (human not PC) and I've been taking it slow.

September.

20th. Extruder works.

The extruder works. It needs some tweaking to insulate the sensor wires from the hotend.
Some of my ducting melted but no show stopper.
I extruded some ABS and it looks good.

I'm hoping for the new PCBs in two weeks along with some other parts.
I think it will take a week to put everything together and do the first test print.

I've also redone some of the electronics case CAD I lost in the crash. This will be the first big print for Huey if he is up to it.

15th.

I've had a frustrating time compiling and uploading to repetier firmware.
I got it mostly working a few days ago but had crazy stuff happening with the Z-limit signal from the go-between board.
The board works but repetier would ignore it - but sometimes a finger in the right place would get it too work.
Trying all the usual stuff but in the end it was solved with intuition not logic.

The firmware seems to be reading the Y-stop pin instead of the Z-stop pin.
Presumably an error in pins.h but strange that no-one else is complaining.

9th.

One Y motor seems faulty but the two X motors seem to work perfectly.
The little steppers seem to have enough power but I haven't tried with the weight of the extruder.

8th.

Two Z motors running and the homing logic seems OK but repetier isn't responding to the signal.
I will need to install arduino IDE and jump throught the compile upload hurdles again.
I lost my current config in the drive crash so I have to do it all again.

Testing the X or Y motors is probably more important because I may need to order bigger motors.

6th.

New PCB submited to dirtyPCBs for fab.
I found several bugs in version-1 mostly in my arduino footprint.
I added options for a seperate 5V regulator, LEDs and some unnessecary protection resistors.
V1 has only been tested with one z-motor so far and runs OK at 6400 microsteps/sec (2 rmp).
The Z motors look like they will work but the drivers get hot and really need some fan cooling.

The motor was controlled by repetier host on my netbook talking to repetier firmware in a teensylu.

The step,direction and enable signal were taped at empty driver socket on the teensylu and jumpered to my PCB.
The basic idea seems to have legs.

2nd.

Some progress but not all good.
The carriage and hot-end was made a few weeks ago but I'm leaving the heater and sensor off till I have the carriage moving.
I recovered a fairly up to date copy of the PCB artwork and brought it up to date.
However when I powered up my prototype PCB I had trouble with an FEC (flame emmiting capacitor).
No mystery there as I had it reversed but no idea why a second cap charred and the arduino died.
A replacement arduino also died.
I've done a new version of the PCB artwork but until I know why the current one is failing I won't submit it for manufacture.

The flame out co-incided with me catching a virus (human not PC) and I've been taking it slow.

August.

7th.

Making some progress again.
Printrbot is working on the new PC.
After installing the new version of repetier host PLA is printing better than before the crash.
ABS is not printing well but that is fairly normal and ABS doesn't like the cold.
I redid the CAD files for the printhead carriage and I think it is better than the one I lost.
However it didn't print well in ABS.
Only a small part needs to be ABS so I'm rethinking the design and will probably split the part so the bulk is PLA.

July.

27th minor disaster.

I had a disk crash last night. Probably a month set back. Not only did I loose a lot of files but I also have to set up a new PC.
My XP box is now dead.

19th

I got the repetier firmware compiled after jumping through all the required hoops.
I still couldn't get the bootloader(s) to work and programmed the usb1286 with an ISP programmer.
That had issues as well - I had to 1/2 the programmer clock speed before I could read the correct device ID and enter programming mode.
The firmware runs and talks to the host but there will probably be a few more times through the compile/upload cycle before all the options are correct.
First time around the hotbed sensor didn't work and I had to edit Configuration.h

18th

Two set backs.
The PCB footprints for the stepper driver modules are too wide - 0.6 inch instead of 0.5
Not a show stopper just ugly. I've fixed the PCB artwork.

Next the Teensylu arrived but I haven't managed to compile or upload code into it.
I can't download "Arduino 1.0.5" for some reason and it is the only version supported by teensyduino.

17th

The go-between PCBs have arrives from dirtyPCBs and look good.
The hot-end kit is here but I haven't opened the box yet.
Still short on connectors and cables but I can make a start on testing my boards.
I also made (printed) a mount for the PSU.
I'm part way through designing the case for the electronics but it is 450mm long and can't be printed on my small printer.

9th

Designed, printed and fitted temporary limit switch carriers and Z-micro switch landing area.
All ad-hock because the next generation z bearing assembly will incorporate them.
I decided to put the Z-switches on the Z carriage not the base.
There are already X and Y switches mounted there so I may as well run the cables together.

5th

3rd

PCBs are in the mail.
I also wrote the code for them but not tested yet.
In the last few days I designed the belt coupling for the X and Y rods ends.

I noticed a difference in belt positions between X and Y belts.
This turned out the be because the Z-bearing assemblies are drooping.
I don't think this is a show stopper and the next version will be larger and more stable.

June.

27th

The homebrew PCB didn't happen due to an aerosol can failure.
So I ordered 10 dirty PCBs on the 25th from http://dirtypcbs.com
Worst case delivery could be 8 weeks but if I'm lucky it will be less than 1/2 that.
I also started writing the code for it and noticed a minor problem.
The AVR pin-change interrupts can't be used to detect only rising edges (they detect both edges).
Fixing this in software would slow things down so I'll just short the pin change input (a5) to int0 (d2).
I'll also add a "homed" LED if I ever update the artworks.

23rd

Ordered a Teensylu v0.8 because it has easy access to the signals I need. Uploading the firmware looks like a pain though.

Phil is going to try making a DIY PCB for me in the next few days. If it works I'll be ordering some dirtcheap PCBs.

22nd - Go between PCB.

I've done very little on the mechanical stuff and worked on the control stuff.
I wanted to move away from using EAGLE for the PCB stuff because of the board size limitation of the free version.
I wasted quite a lot of time trying to install linux mint 16 so I could try jEDA as an alternative. After many installer failures I move to windows Kicad instead. It has its quirks and annoyances but it one of the easiest PCB packages I've used. Today I finished the first version of the go-between board.
See the main page for more info on what that is.

May

30th

23rd

All four Z-bearing assemblies are hanging off the threaded rods. Only one Z-motor fitted ATM.
Tolerances around the Z motor couplings are tight and I went through many revisions to get it rotating freely.

18th

All Z-bearing assemblies installed including the four motors and four idlers.
I also worked out how I can (eventually) use eight limit switches and eight stepper controllers with a printrboard.

16th

I had problems with a warped wooden bed on the printrbot and had to make mods to fix it.
I have since printed 4 versions of the two bearing Z assembly.
They are fitted and look Ok except the 12mm rod holes are a little shallow.
I deepened them to 15mm in the model and deepened some physical hole with a 12mm drill.

6th

I fought with Sketckup for 3 long days converting the Z bearing thing to a two bearing version.
Only Sketchup users know how hard it can be to fix a model that has gone bad.
In the process I converted to sketchup "make" version and "solid inspector" plugin saved me hours.

Also made a new printbed for the printrbot and it is too uneven to use - yet another job to do.
So the two-bearing design is ready to print but will have to wait till I have a new bed.

3nd

Well that was pretty basic. One bearing was being jammed by the end of the motor shaft.
Either the motor is moved back, the motor is moved sideways or the shaft is shortened.
I think I will go with option two. The motor plate probably needs tweaking anyway.

I'd still like to try a two (not four) bearing version of the Z bearing thing.

Pretty much wasted a day trying to modify the art work for two bearings - it it a mess and not even 1/2 done.

The new motor plate has a problem with access to one motor screw - can live with that for the beta.

I thought it might be the belt tension twisting the assembly but that isn't it. Will investigate tomorrow.
It is possible the inner bearing may not be needed.
This assembly was dropped a few weeks ago and may be damaged.
It is printed in PLA and had issue with the bridges and these sags may be interfering with the bearings.